Saturday, June 28, 2008

For us that read globally scientific papers of significance, while evaluate its quality, the biography of their producers and the organizations of their workplaces, surprise us the reemergence of the scientific framework in Germany. If USA is great in this aspect, Germany has now the same. We say this because the magic of the Internet has enabled us to make visits to these centers of excellence. It is not just only, the prestigious Max Planck Institute(craddle of germans Nobel Prize), but also of others, reason for what we introduce –as an example of the previous- to Magdalena Götz(Institute of Stem Cell Research/Helmholtz Zentrum/Munich) and colleagues of the Ludwig's Maximilians-University/Munich, 2 notable German research centres. Götz and his team show as thorough (with photographs and molecular determinants of development of the cerebral cortex), the conversion process of glial cells (support neurons tissue: precursors, microglia and astrocytes), to stem cell first (dedifferentiatión)and then to new nerve cells, after severe brain insults.

To test the previous, Götz conducted genetic mapping and targeting specific viral, demonstrating how quiescent astrocytes proliferate after an insult conditioning a reactive gliosis, including proliferating GFAP cells, revealing their multipotency and self renewal capacity, forming neuroespheres(embryos of new nerve cells), in the brain cortex of adult mice. Although it was known that reactive gliosis is the universal reaction to the brain insult, Götz demonstrates how the astrocytes in front of it, hypertrophy its somata and dendritic processes, activated protein-glial fibrillary acidic protein (GFAP) and to a subpopulation of GFAP reactive cells, from glial endogenous parents and certain mature proliferating astrocytes, restoring tissue integrity, reducing inflammation and neuronal death. As it is known, mature astrocytes, oligodendrocytes and neurons are permanently postmitótic cells, not given to proliferation. In contrast, reactive proliferating cells, originated in GFAP astroglial precursors resume proliferation after an insult, implying dedifferentiatión towards immature cells in certain brain areas (adult stem cells), while other groups dedifferentitate toward earlier stages of development similar to those postnatal or embryonic brain states.